1. Field of the Invention
The invention relates to a speaker.
2. Description of the Related Art
Conventionally, various types of speakers have been commonly used wherein a speaker has a baffle fitted with a speaker unit, and a cabinet that covers the back of the speaker unit and is screwed on the baffle (see JP-A-2003-289592).
Furthermore, a speaker having a packing for sealing an abutting part between the baffle and the cabinet is also known.
A speaker 1 shown in FIGS. 1 and 2 is a box-type woofer, which includes a baffle 3 fitted with a speaker unit 10, a cabinet 5 that covers an opening of the baffle 3 at the back of the speaker unit 10 and is screwed on the baffle 3, a plurality of screw hole bosses (mounting bosses) 11a to 11e and 12a to 12e, which are projected on the baffle 3 at an abutting part between the baffle 3 and the cabinet 5, and sound insulating packings 7 and 8, which are set between the baffle 3 and the cabinet 5 at the abutting part to seal the abutting part.
A sealing area formed on such an abutting part between the baffle 3 and the cabinet 5 takes the shape of a rectangular mold form. Meanwhile, a packing of a given shape is usually punched out of a sheet-like packing material. When the packing is punched out of such a material into a rectangular mold form, the yield of the packing material becomes low and a molding die is required to be larger, thus the manufacturing cost of the packing increases.
To suppress such a cost increase, the sealing area, which is of a rectangular mold form, is divided into two similar L-shaped sealing areas A and B, and a pair of the sound insulating packings 7 and 8, each having an almost L-shaped outline, are provided in correspondence to the L-shaped sealing areas A and B, as shown in FIG. 1.
Meanwhile, cylindrical screw hole bosses 11a to 11e and 12a to 12e, which are projected on the baffle 3, are often arranged to be non-symmetrical to each other in order to specify a mounting direction of the cabinet 5 to be screwed.
For example, as shown in FIG. 3, the projected positions of the screw hole bosses 11a, 11b, 11c and 12a, 12b and 12c, which are most of the entire screw hole bosses, are determined to be point symmetrical to each other in the two similar sealing areas A and B on the opening edge of the baffle 3, on which the sound insulating packings 7 and 8 are placed.
However, a gap Wa between the screw hole bosses 11d and 11e on one long side of the baffle 3 is made different from a gap Wb between the screw hole bosses 12d and 12e on the other long side of the baffle 3 in order to specify the mounting direction of the cabinet 5. As a result, the projected positions of the screw hole bosses 11d and 11e and that of screw hole bosses 12d and 12e are determined to be non-symmetrical in the similar sealing areas A and B, respectively.
Mounting holes 7a to 7f and 8a to 8f are formed on the sound insulating packings 7 and 8, respectively, and are made into a circular shape that correspond to the sectional shape of the screw hole bosses 11a to 11e and 12a to 12e, which are inserted into the mounting holes. To make adjustment for the difference in the projected positions between the screw hole bosses 11d and 11e on the one long side and the screw hole bosses 12d and 12e on the other long side, a gap between the mounting holes 7d and 7e on the sound insulating packaging 7 and a gap between the mounting holes 8d and 8e on the sound insulating packing 8 are made different in correspondence to the difference between the gap Wa and the gap Wb.